Load a supplementary dataset distributed with countrycode.

Load a supplementary dataset distributed with `countrycode`.

def load_dataset(
  name: str,
  as_type: Literal["dict", "pandas", "polars"] = "dict"
)

`name`	Dataset name. Valid values are `"codelist_panel"`, `"countryname_dict"`, and `"cldr_examples"`.
`as_type`	Output representation: `"dict"`, `"pandas"`, or `"polars"`.

A mapping of column names to lists, a Pandas DataFrame, or a Polars DataFrame, depending on as_type.

`ValueError`	If `name` or `as_type` is invalid.
`ImportError`	If the requested optional DataFrame library is not installed.

panel = load_dataset("codelist_panel")
len(panel["year"]) > 1000